Thomas & Friends: Big World! Big Adventures! is a 2018 animated children's musical adventure film in the Thomas & Friends franchise. The fourteenth and final feature-length special in the Thomas & Friends television series, it follows Thomas the Tank Engine as he aims to become the first steam locomotive to go all the way around the world. John Hasler and Joseph May reprise their roles as Thomas in the British English and American English dubs respectively, while Peter Andre and Yvonne Grundy join the cast.

The film was announced in 2017 as part of Mattel's planned "big makeover" of the series, with the aforementioned company partnering with the United Nations to incorporate their Sustainable Development Goals into the film.

Thomas & Friends: Big World! Big Adventures! saw a limited theatrical release in the United Kingdom on July 20, 2018, receiving negative critic reviews and grossing US$3.2 million at the box office.